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951.
The objective of this study was to investigate the influence of orally administered biotin on the healing of uncomplicated sole ulcers in dairy cattle. In a double-blind controlled study, 24 dairy cows with a mild, uncomplicated sole ulcer on a lateral hind claw were given either 40 mg biotin per day or a placebo feed over a period of 50 days. An orthopaedic shoe was fitted to the medial claw of the affected foot. The healing process was assessed clinically and by histological examination of horn samples. In the biotin-treated animals, the newly formed epidermis covering the sole ulcers was found to be of significantly better histological quality after 50 days than at the start of the study. The significant improvement in histological horn quality found in the biotin-treated animals suggests that biotin exerts a positive influence on the healing of sole ulcers, however the study period of 50 days appears to have been too short to permit macroscopic detection of the improvement in horn quality.  相似文献   
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DNA diagnosis in veterinary medicine: II. Polymerase chain reaction (PCR)   总被引:1,自引:0,他引:1  
DNA diagnostic has become very important for genetic and infectious diseases. With a new method, called the polymerase chain reaction (PCR), specific pieces of genomes from viruses, bacteria, parasites or even cells can be amplified more than hundred million fold in a very short time period. For the following reasons this opens a new dimension in diagnostics: (1) The technique is so sensitive that a single virus, bacterium, parasite or cell is sufficient to be detected provided part of its nucleic acid sequence is known. (2) The material does neither need to be fresh nor be stored under special conditions since the nucleic acids are much more stable than e.g. enzymes or other proteins. (3) The method is quicker than the usual immunodetection methods. (4) The polymerase chain reaction has been standardized recently so that it can be carried out in diagnostic laboratories. The purpose of this minireview is to give an introduction into the basic technique and to mention possible and already existing applications in veterinary medicine.  相似文献   
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A total of 44 live cheetahs were examined sonographically between 1989 and 1994. Seventeen of these animals originated from 4 European facilities, the other 27 cheetahs were examined in 3 facilities in Namibia. Evaluation of the cheetahs included a clinical examination, abdominal ultrasound, and complete blood work. Splenic myelolipomas were diagnosed sonographically in 11 cheetahs. In 7 cheetahs the diagnosis was confirmed at necropsy. Nine of the 14 cheetahs in Europe had myelolipomas in the spleen, while in the African cheetahs there were only 2 animals with myelolipomas. Histologically these lesions were characterized by fatty nodules. A more fitting term of Nodular Lipomatosis of the spleen is therefore suggested. All cheetahs with nodular lipomatosis of the spleen, had concurrent chronic diseases at necropsy. An indicator function of splenic nodular lipomatosis for chronic disease and/or stress is possible.  相似文献   
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